What do surge tanks help maintain in a water distribution system?

Surge tanks play a crucial role in water distribution systems by helping to maintain flow stability during fluctuations in water demand. They provide a buffer against sudden changes in pressure caused by varying demand, such as when large quantities of water are drawn from the system or when pumps start and stop. By accommodating these changes, surge tanks help to prevent pressure surges that can damage pipes and equipment, ensuring a smooth and stable flow of water throughout the system.

The other options, while relevant to different aspects of water distribution, do not relate directly to the primary function of a surge tank. Constant temperature is generally regulated through other means in a water system, contaminants are filtered and treated through dedicated systems, and energy consumption reduction is a goal achieved through various system efficiencies but is not specifically tied to the mechanism of surge tanks. Thus, the contribution of surge tanks to maintaining flow stability is essential for the overall health and efficiency of a water distribution system.